Elapsed time speed check arrangement



April 11, 1961 J STRQBEL 2,978,863

ELAPSED TIME SPEED CHECK ARRANGEMENT Filed Feb. 6, 1957 3 Sheets-Sheet 1 I April 11, 1961 J STROBEL 2,978,863

ELAPSED TIME SPEED CHECK ARRANGEMENT Filed Feb. 6, 1957 3 Sheets-Sheet 2 I20 6 72 Z07 agrifiurzffzrolel April 1961 A. J. STROBEL 2,978,863

ELAPSED TIME SPEED CHECK ARRANGEMENT Filed Feb. 6, 1957 3 Sheets-Sheet vIS United. Sta s Patent ELAPSED TIME SPEED CHECK ARRANGEMENT Arthur J. Strobel, Topeka, Kans assignor to Eltic, Inc., a corporation of Kansas Filed Feb. 6, 1957, Set. No. 638,528 6 Claims. (Cl. 58145) This invention relates to an elapsed time measuring device for checking the speed of vehicles and more particularly is concerned with an arrangement for making spot checks of the speed of trains at various selected points of a railway system.

Spot checking of train speeds is carried out by railroads to assure that the trains are observing the safe speed limits established by the roads and the checks, to be etfective, must be taken at unexpected times and places. *Frequently the checks must be taken at remote and relatively inaccessible spots and all of this places a premium on lightweight portable equipment that is accurate and reliable.

Electromagnets controlled by suitably spaced apart track switches have been used for automatically starting and stopping a timing mechanism for measuring the time required for a train to traverse the distance between the switches. Since the distance is predetermined or readily ascertainable, the elapsed time is a measure of the train speeds. In the prior art, the armatures of the electromagnets have actuated the operating stem of a stop watch but due to the relatively large power requirements of this type of application, the associated battery and connecting wires have necessarily been of substantial size and the entire apparatus is bulky and difiicult to transport. It has also been difiicult, under the rugged conditions of field use, to maintain a reliable action between the watch stern and the actuating arm that is controlled by the electromagnets.

The present invention has for its principal object the provision of an improved arrangement for controlling a timing mechanism with an electromagnet: that provides a direct connection between the armature of the electromagnet and the actual clockwork mechanism for controlling starting and stopping of the timing mechanism; that requires a minimum of operating power thus permitting the use of small size batteries and wires; and that is independent of the direction of travel of the vehicle being checked.

Briefly this is accomplished by providing a single electromagnet that is energized only during the time when the vehicle being checked is traversing the distance between the controlling switches. The electromagnet is mounted directly on the cover of a watch and a control member carried by the armature projects through the watch cover into precise engagement with the balance wheel and escape wheel of the clockwork mechanism. When the electromagnet is not energized, the control member is in its locking position and prevents operation of the clockwork mechanism but upon energization of the electromagnet, the armature shifts the control member to its release position to start the clockwork mechanism and maintain it so long as the electromagnet remains energized.

A versatile circuit arrangement I and track switch mounting arrangement control the energization of the electromagnet..

Other objects and advantages of the invention'will beelectromagnet irrespective of the order in which the switches are actuated;

Fig. 4 is an enlarged perspective view, with parts broken away and sectioned, of the preferred arrangement for connecting the controlling electromagnet to the clockwork mechanism of a watch for starting and stopping the watch;

Fig. 5 is a fragmentary plan view, with parts broken away better illustrating the precise mounting relationship between the shiftable control pin and the clockwork mechanism;

Fig. 6 is a side view with parts broken away illustrating the mounting of the watch in a protective housing and better illustrating the attachment of the controlling electromagnet to the watch; and

Fig. 7 is a rear view of the watch and its mounting plate.

Referring now to the drawings, and particularly to Fig. 1 thereof, the speed check arrangement of the invention, as shown applied to a track rail R for spot checking of train speeds, includes a pair of track switch devices 10 and 11 spaced apart a suitable distance along the rail and actuatable by the front wheels of a train for energizing a circuit during the interval when the train is traversing the distance between the switches. The energizing circuit of Fig. 3 includes an electromagnet 12, a battery 13 for supplying operating power and an ON-OFF switch 14. The electromagnet is arranged to control the starting and stopping of the clockwork mechanism of a Watch 15 or other suitable timing mechanism.

The watch 15 is shown mounted in an individual housing 16 Fig. 6) having a hinged cover leaf 17 that folds out for viewing the face of the watch. Preferably the watch housing 16 is removably mounted in a carrying case 18 which also receives the battery 13, the battery compartment being located behind the panel 19 which carries the OFF-ON switch 14. As indicated at 20, the carrying case preferably provides ample storage space for receiving the track switch devices and the necessary connecting plugs and wires.

Each switch device preferably includes a weatherproof housing 22 for the electrical switches and the housings are provided with suitable plug receptacles to facilitate the connection of the circuit components in the field. The housings are carried by an upstanding arm 23 of a suitable rail clamp 24 which is slipped over one edge of the base or" the rail R and engaged by a suitable wing nut 25 carried at one end of a combination bolt and clamp 26. The opposite end of member 26 is formed with a rail gripping clamp portion 27 that terminates in a hook loop 28.

Each switch is preferably of the single pole, double throw type in which there is provided a normally open contact 30, a normally closed contact 31 and a common contact 32 movable between contacts 30 and 31. The actuating arm 34 for each switch is biased to project outwardly through its housing. Each housing also includes a hook 35 which is preferably located directly beneath the outwardly projecting actuating arm 34 and a familiar rubber band 36 or other rubberlike tension member is pulled tightly across the top surface of the rail R and connected at its opposite ends to hooks 28 and 35. As shown in Fig. 2 the free end of the actuating arm 34 is wing-shaped to form a saddle in which the tensioned rubber band 36 is engaged. The tension on the rubber band gormally holds arm 34 in against the action of its spring ias.

Thus with the rubber band connected, as shown in Fig. 2 to hold the switch actuating arm 34 against outward movement, the normally open contacts 30 or" each switch, as shown in Fig. 3, are isolated and the normally closed contacts 31 are engaged with their associated common contact. The switches are connected in series with the normally open contact of switch 10 connected to the normally closed contact of switch 11 and vice versa, the common contacts being connected together. Thus, when rubber band 36 restrains the actuating arms 34, the cir-' cuit is open and electromagnet 12 is deenergized. However, upon the passage of a train from either direction the switches 10 and 11 are actuated successively and electromagnet 3.2 is energized during the interval when the train is traversing the distance between the switches. It frequently happens that in making spot checks of train speed, one has no knowledge of the direction in which a train will pass and it becomes quite important that the detecting device be capable of functioning irrespective of the order in which the switches are actuated.

In making speed checks with stop watch arrangements, it has been found convenient to locate the switches a constant predetermined distance apart in order that the elapsed time indications on the watch may readily be converted, by means of a simple chart, into measurements of train speed. For example, it is particularly convenient to use switch spacings of 44 feet, or multiples thereof, but not infrequently the location of the cross ties may hamper the original installation or" the switches. The first switch to be installed might be located intermediate a pair of ties but when the 44 foot spacing distance is measured out, it may happen that a tie prevents the exact spacing desired. In the past it has always been necessary to relocate the first switch but the construction of the present invention substantially eliminates this annoyance because the rubber band may be displaced from its intended alignment by as much as two or three inches in either direction without impairing its controlling action on switch arm 34. This allows a degree of flexibility in the actual switch location and also permits the desired distances to be very accurately marked off with a minimum of adjustment.

A particularly important advantage of the invention resides in the fact that very small amounts of power are required for actuating the electromagnet 12. For example, a current of as little as /2 ampere through a six volt circuit has been found to be quite adequate. These small current requirements permit the use of small conductors and No. 22 A.W.G. very adequately handles the currents involved. As a matter of fact, considerably greater switch spacings are possible with the same basic power supply and conductor size and spacings of as much as 200 feet are readily accommodated. One should also hear in mind that the carrying case shown at 18 in Fig. l is more than ample for handling all the necessary gear though the dimensions of this case may run as small as 10" x 8" x The weight of the case when fully packed runs on the order of 12 lbs.

These factors of portability and ease of installation are of the utmost importance to the operating personnel as they must frequently use this equipment under difiicult weather conditions at relatively inaccessible and isolated check points. The check points must be continuously varied in order to retain the element of surprise so necessary to an efiective check system. With these points in mind, the advantages of the compactness and light weight of the present invention can be better appreciated.

In Figs. 4 to 7 the particular arrangement for controlling the starting and stopping of a clockwise mechanism with minimum power requirements is shown as comprising the electromagnet 12 which carries a generally U-shaped control member 40 that projects through registering slots 41 and 42 formed in the outer and inner back covers 43 and 44 respectively of the timing device 15 which is shown here in the form of a stop Watch having the usual winding stem 45 and having a conventional clockwise mechanism that includes an escape wheel 46 driving a balance wheel 47 through the pallet fork connection 48.

The timing device preferably is a Meylen second timer No. 211 distributed by the Meylen Stop-Watch Company, New York, New York, it being extremely sensitive in that its balance wheel makes oscillations each second whereas the balance wheel of the average watch used in time keeping operations makes. only five oscillations per second. Normally this watch is operated to positions of start, stop and return by successive depressions of the crown but for use with the present invention the start and stop lever and associated spring have been removed and the slots 41 and 42 are formed in the back covers to receive the control pin 40. As modified, the crown still controls the return operation.

The electromagnet 12 that is used is model P.S.N. distributed by Citizen-Ship Radio Corp, Indianapolis, Indiana, though it too is modified in that the soft metal armature arbor has been replaced by a steel arbor, the tip of which is shown at 50 in Fig. 4. Preferably brass bushings (not shown) are provided for the ends of the arbor 50 to assure closer tolerances. In addition the electromagnet carries an armature extension 51 that is formed with an elongated slot for the mounting screws 53 to accommodate adjustments of the armature extension such as may be necessary to facilitate the necessary precise adjustment of the control pin 40. Towards this end, the free end of extension 51 carries guide flanges 54 for the control pin which is secured therebetween in adjustable relation by a screw 55. Thus, two degrees of adjustment of the control pin are provided.

To stabilize the mounting location of the control pin 40 relative to the clockwork mechanism of the watch, it is preferred to mount the electromagnet 12 directly to the outer back cover 43 of the Watch. For this purpose a suitably formed bracket 56 is employed.

The control pin is made of spring steel wire bent into a U-shape so that the arm 60 that engages the escape wheel 46 is slightly longer than the arm 61 that engages the balance wheel 47. The electromagnet, as shown in Fig. 4 is in its deenergized position, in which case the control pin 40 is in its locking position as shown in full lines in Figs. 4 and 5. When the electromagnet is energized, its armature moves the control pin to its release position which is shown in dotted lines in Figs. 4 and 5. Upon deenergization of the electromagnet, a return spring 62 (Figs. 6 and 7) drives the armature back to its original position.

The control pin is very precisely located so that when it is in its locking position arm 60 engages the escape wheel and the arm 61 is clear of the balance wheel. As the control pin moves from its locking position to its release position, arm 60 moves free of escape wheel 46 and arm 61 gently brushes the balance wheel 47 to set it in motion. Upon return movement to the locking position, arm 61 again brushes against the balance wheel and has a tendency to stop its movement momentarily, particularly if it is moving in a direction opposite to that of the arm 60 at the instant of contact, while arm 60 engages the'escape wheel and locks the clockwork mechanism against further actuation.

It is preferred to mount the watch and electromagnet assembly within a suitable housing 16 and this is accomcanvases plished by removing the usual hinge pin from the outside back cover 43 of the watch and permanently securing this cover toa mounting frame 63 which then is anchored in the housing'16 by suitable fasteners 64. Preferably a plurality of brackets 65 are rigidly soldered in position to hold the cover 43 rigid with the mounting frame 63. Finally the watch proper is secured to the outer back cover by means of a holding yoke 66 (Fig. 6) which grips the stem of the watch to the mounting plate, and a pair of holding clamps 67 which grip the casing of the watch to the mounting plate. Suitable screws 68 are used with the holding yoke 66 and clamps 67 to permit ready removal of the clockwork mechanism.

'Briefly the overall operation of the apparatus of the invention is as follows: As a train approaches, its lead wheel severs the rubber band of the closest switch causing this switch to close the circuit of Fig. 3 and energize electromagnet 12 which moves from its full line locking position of Figs. 4 and 5 to its dotted line release position, thus actuating the clockwork mechanism. As the train travels between the switches the circuit remains energized and the control pin remains in its release position and allows the timing device to operate continuously. When the train reaches and severs the rubber band for the remote switch the circuit is interrupted thereby deenergizing the electromagnet and permitting the return spring to move the control pin back to its locking position.

It will be understood that the advantages arising from the low power requirements of the present clockwork control arrangement are equally important in speed check arrangements such as might be used for checking the speed of automobiles. Obviously appropriately different forms of control switch arrangements would be required in such instances but the features of portability, compactness, accuracy and reliability would still be present in full vigor.

It should be understood that the description of the preferred form of the invention is for the purpose of complying with Section 112, Title 35 of the United States Code and that the appended claims should be construed as broadly as the prior art will permit.

I claim:

1. In an elapsed time measuring apparatus for automatically checking the speed of a vehicle traversing a path of known length, the combination of a watch having clockwork mechanism including a balance wheel, shiftable means in said watch, operable externally thereof and movable from a release position to a locking position and vice versa, said shiftable means when in locking position positively preventing said clockwork from being operated, and when being moved from locking position to release position tangentially engaging the periphery of said balance wheel to start it and said clock mechanism in operation, electromagnetic means including an electromagnet and an armature, said armature being operatively secured to said shiftable means whereby when said electromagnet is energized, said shiftable means is moved to its release position and when de-energized said shiftable means is moved to its locking position, and an energizing circuit for controlling operation of said electromagnet, said circuit including a power source in series with said electromagnet and a pair of switches separately located at opposite ends of said path for operation successively by a vehicle traversing said path, the switch at the vehicle entering end of said path being normally open, and said other switch being normally closed whereby said circuit is energized only during that period of time that the vehicle is traversing said path of known length.

2. The elapsed time measuring apparatus as set forth in claim 1 in which each of said switches is of the single pole, double throw type.

3. In an elapsed time measuring apparatus for automatically checking the speed of a vehicle traversing a path of known length, the combination of a watch having clockwork mechanism including a balance wheel, shiftable means in said watch, operable externally thereof, and movable from a release position to a locking position and vice versa, said shiftable means when in locking position positively preventing said clockwork from being operated, and when being moved from locking position to release position tangentially engaging the periphery of said balance wheel to start it and said clock mechanism in operation, electromagnetic means including an electromagnet and an armature, said armature being operatively secured to said shiftable means whereby when said electromagnet is energized, said shiftable means is moved to its release position and when de-energized said shiftable means is moved to its locking position, and an energizing circuit for controlling operation of said electromagnet, said circuit including a power source in series with said electromagnet and the common contacts of a pair of single pole, double throw switches separately located at opposite ends of said path and operated successively by a vehicle traversing said path, each of said switches having a normally open contact and a normally closed contact, with said common contact engageable with either of said first-mentioned contacts individually, conductor means connecting the normally open contact of one of said switches to the normally closed contact of the other switch, conductor means connecting the normally closed contact of said one switch with the normally open contact of said other switch, the circuit arrangement being such that a vehicle traversing said path in either direction causes the electromagnet to be energized only during that period of time that the vehicle is traversing said path of known length.

4. In an elapsed time measuring apparatus for aut0- matically checking the speed of a vehicle traversing a path of known length, the combination of a watch having clockwork mechanism including a balance wheel, shiftable means in said watch, operable externally thereof, and movable from a release position to a locking position and vice ver'sa, said shiftable means when in locking position positively preventing said clockwork from being operated, and when moved from locking position to release position starting the clock mechanism in operation, electromagnetic means including an electromagnet and an armature, said armature being operatively secured to said shiftable means whereby when said electromagnet is energized, said shiftable means is moved to its release position, spring means biasing the armature and shiftable means to the locking position of said shiftable means, and an energizing circuit for controlling operation of said electromagnet, said circuit including a power source in series with said electromagnet and a pair of switches separately located at opposite ends of said path for operation successively by a vehicle traversing said path, the switch at the vehicle entering end of said path being normally open, and said other switch being normally closed whereby said circuit is energized only during that period of time that the vehicle is traversing said path of known length.

5. A start and stop control for a clockwork mechanism of the type that includes an escape wheel driving a balance wheel, said control comprising an actuating arm having a control pin fixed thereon, means mounting said actuating arm for pivotal movement about a point spaced from said pin to accommodate reversible swinging movement of said pin from its release position wherein it is free of said balance wheel and escape wheel, through an intermediate position wherein it momentarily engages the periphery of the balance wheel, and to its locking position wherein it engages the periphery of said escape wheel and is clear of the balance wheel, resilient means reacting between said mounting means and said actuating arm to bias said pin to its locking position and yieldingly resist swinging movement of said pin from its locking position to its release position, and means for operating said actuating arm to swing said pin against the action of said resilient means to move said pin from its locking position, through its intermediate position, and to its release position for releasing said escape wheel and cause saidpin to tangentially brush the periphery of the balance wheel to thereby set it in motion.

6. A start and stop control for a clockwork mechanism of the type that includes an escape wheel driving a balance wheel, said control comprising an actuating arm having a pair of pin-like control elements fixed thereon, means mountingtsaid actuating arm for reversible movement to carry said elements along a path from a release position wherein both are free, through an intermediate position wherein one element momentarily engages the periphery of the balance wheel and the other element is free, and to a locking position wherein said other element engages the periphery of the escape Wheel and said one element is free, resilient means reacting between said mounting means and said actuating arm to bias the arm to its locking position and yieldingly resist movement of the arm from its locking position to its release position,

and means for actuating said arm to move the arm- References Cited in the file of this patent 7 UNITED STATES PATENTS 450,966 Matthews Apr. 21, 1891 1,498,749 Porter June 24, 1924 2,208,721 Demosthenes July 23, 1940 12,292,908 Terrill Aug. 11, 1942 2.325,312 Follender July 27, 1943 2,480,760 Morse Aug. 30, 1949 2,559,796 Rath July 10, 1951 2,607,866 Fruh Aug. 19, 1952 2,675,667 Schlenker Apr. 20, 1954 

